For more than 70 years, the Denver Art Museum has been an iconic landmark for the city’s arts and cultural community.
Every year, more than 700,000 visitors experience the museum’s award-winning exhibitions, art collections and hands-on programs for all ages, making it one of the top 20 most-attended art museums in North America.
In 2014, a fundraising effort to renovate the museum’s north tower began. Now named the Martin Building after receiving a $25 million gift from Sharon and Lanny Martin in 2016, the seven-story, 229,000-square-foot structure was designed by Italian architect Gio Ponti and Denver-based James Sudler Associates.
In January 2018, a groundbreaking ceremony was held to celebrate the project that incorporates elements of Ponti’s original concept, expands gallery spaces, provides a new conservation laboratory, and increases the museum’s capacity to provide educational programming while improving campus connectivity and building systems.
Thanks to a $12 million gift from Anna and John Sie to support the revitalization effort, the project was expanded to include the addition of the Sie Welcome Center just outside the Martin Building. Designed by architecture partners Fentress Architects of Denver and Machado Silvetti of Boston, with a nod to Ponti, the 50,000-square-foot elliptical-shaped glass structure complements the city scape and provides an exterior work of art for Colorado.
On the one-of-a-kind curved-glass curtain wall system,
The project’s general contractor, Saunders Construction, Denver, selected Douglass Colony Group Inc., Commerce City, Colo., to install standing-seam copper panel and PVC thermoplastic membrane roof systems.
“When Douglass Colony Group had the opportunity to design the roof systems for the unique Sie Welcome Center, we recognized the importance of honoring the museum’s creativity and used innovative solutions for the project,” says Aaron Harvey, senior project manager for Douglass Colony Group.
The Douglass Colony Group team began work on the project in November 2018. Because the Sie Welcome Center’s structure has such a unique shape, fabricating the metal panels and internal gutter system were especially challenging. To succeed, the crew implemented what it learned from working on the Colorado State Capitol building.
“We were able to determine the similarities between the two projects and demonstrate how the state capitol building had several finished qualities that met the criteria for the goals of the Denver Art Museum,” Harvey explains. “We used a similar approach to materials and used the experience we learned from the Colorado State Capitol installation to successfully create a fully functional, true piece of art.”
The team selected to work on the Denver Art Museum also was the same team that worked on the Colorado State Capitol.
“A project that bears such enormity and importance to the city of Denver requires outstanding workmanship, not only from the on-site roofing workers but also from those in management to successfully execute a project,” Harvey says. “By intentionally choosing to use the same team, we were able to charge forward with the Denver Art Museum project at a much quicker and more efficient pace.”
For example, when sporadic winter weather unexpectedly delayed work on the Denver Art Museum, the experienced Douglass Colony Group team knew to quickly assemble multiple crews to work with other trades to get the roof area dried in and create a temporary roof system. When the permanent structure was completed, the team worked dual shifts to meet expedited daily delivery dates.
Using a combination of uncommon materials, the Douglass Colony Group crew designed creative roof systems that lend memorable additions to the Denver landmark.
The standing-seam panel roof system on the Sie Welcome Center was designed in a fan shape. On the 8,800-square-foot metal roof deck, workers set 5/8-inch-thick DensDeck® Prime Roof Boards in adhesive followed by a layer of self-adhering V-Force™ Vapor Barrier Membrane, a layer of 2.6-inch-thick polyisocyanurate insulation, a layer of 2.6-inch-thick HailGard™ Composite Board, GRACE ULTRA™ underlayment and a layer of Enkamat® for ventilation. To complete the roof system, workers hand-seamed 20-ounce standing-seam Z-T Alloy™ Coated Copper Revere FreedomGray® panels.
“Because the roof substrate was an oblong and inconsistent shape, each panel had to be field-measured and individually fabricated with the right taper and finished on-site to match the contour of the ellipse-shaped roof structure,” Harvey says. “Not one panel was the same.”
In addition, the team installed a custom-curved Alpine SnowGuards® ASG2000B-Mini system.
“A built-in gutter also was designed to provide the proper drainage while not disturbing the visual appearance of the roof,” says Jim Walas, architectural manager for Revere Copper Products Inc., Rome, N.Y. “Detailed edge and fascia design complemented the expansive windows surrounding the art museum. It is critical to align and install the roofing pans without creating stress in the pans or causing surface imperfections with improper handling and storage. There are no signs of misaligned or poorly fitting seams or folds in the large and complicated roof deck.”
For the 9,900-square-foot roof area directly above the one-of-a-kind curved-glass curtain wall system, workers applied a layer of self-adhering V-Force Vapor Barrier over the steel-plate substrate followed by custom-tapered polyisocyanurate insulation to provide slope and a layer of 2.6-inch-thick HailGard Composite Board. Next, workers applied self-adhering GRACE ULTRA underlayment followed by a layer of Enkamat. To complete the roof system, workers installed custom-fabricated 20-ounce scalloped-shaped flat-seam Z-T Alloy Coated Copper Revere FreedomGray panels.
“We had to measure every scalloped panel in the field so each one fit perfectly,” Harvey says. “Because of this, we didn’t have the luxury to wait for any of the roof panels to be made. Our off-site sheet-metal fabrication shop craftsmen went into overdrive and worked overtime and Saturdays to get the panels made as quickly as possible. Fortunately, they were up to the challenge and able to produce the materials in one to two days when our typical fabrication time is two to three weeks.”
During production, Douglass Colony Group craftsmen fabricated triangle-shaped Revere FreedomGray PD30 Alpine Snowguards that were soldered to the scalloped panels, adding to the roof’s aesthetics while serving a legitimate purpose.
“The material was fabricated with great attention to detail, allowing the panels to expand and contract properly,” Walas says. “The panels formed an impressive oval roof deck that is highly visible from various vantage points in the city.”
On the 8,200-square-foot lower roof sections on the Sie Welcome Center, workers applied a layer of Sarnavap® self-adhering vapor retarder to the metal and concrete decks followed by two layers of 2.6-inch-thick R-30 insulation set in foam adhesive. Next, workers set tapered polyisocyanurate insulation and 5/8-inch-thick DensDeck Prime Roof Boards in foam adhesive followed by a layer of TruGround® Conductive Primer for electronic leak detection. To complete the roof system, workers used adhesive to set 80-mil-thick Sarnafil® G 410 EnergySmart Roof Membrane in a custom Denver Grey color.
“We were able to produce an 80-mil custom color to match the metal used on this project,” says Jim Greenwell, Mountain Region manager for Sika Corp., Salt Lake City. “But because of the custom color, Douglass Colony Group workers were challenged in that they had to hand-wrap and weld each penetration flashing to match the roof color. This is not an easy feat for any company.”
On the 6,500-square-foot donut-shaped roof area on the Sie Welcome Center, workers applied a layer of 5/8-inch-thick DensDeck Prime Roof Boards over the metal deck followed by a layer of Sarnavap self-adhering vapor retarder and two layers of 2.6-inch-thick R-30 insulation set in foam adhesive. Next, workers set tapered polyisocyanurate insulation and 5/8-inch-thick DensDeck Prime Roof Boards in foam adhesive followed by a layer of TruGround conductive primer and 80-mil-thick Sarnafil G 410 EnergySmart Roof Membrane in Steeley Grey to match the standing-seam panels.
On the 22,300-square-foot roof area on the Martin Building, workers applied a layer of Sarnavap self-adhering vapor retarder to the metal and concrete decks followed by two layers of 2.6-inch-thick insulation set in foam adhesive. Then, workers set tapered polyisocyanurate insulation and 5/8-inch-thick DensDeck Prime Roof Boards in foam adhesive followed by a layer of TruGround conductive primer and 80-mil-thick white Sarnafil G 410 EnergySmart Roof Membrane.
Working on the Denver Art Museum presented numerous challenges. The construction site neighbors landmark buildings such as the Civic Center Park, Denver Public Library and the existing Denver Art Museum building that cantilevers over Thirteenth Avenue.
To get materials to roof areas, workers had to schedule road closures weeks in advance to make room to set up a crane while ensuring materials were delivered at the precise time needed. This meant the Douglass Colony Group craftsmen fabricating the panels had to remain on schedule so the roof panels were ready to be delivered for the prescheduled lane closure.
“This project was in no way an easy installation of a typical roof system,” Greenwell says. “Starting with the location, Douglass Colony Group did a wonderful job working with our customer service department to get material to the project site in an extremely busy area of downtown Denver.”
The crews worked exclusively from man-lifts and were 100% tied-off for the entire installation.
“Protection of employees and materials were important because of the building’s meticulous nature, large use of concave glass and the standing-seam roof,” Harvey says. “The location and materials used on-site created abnormal working conditions, but our team was able to work through obstacles without incident.”
Colorado’s intense and unpredictable weather patterns also created difficult installation conditions. Because a large portion of the single-ply membrane roof system was installed during cold weather, materials had to be properly stored and covered to be protected from damage. The adhesives used were temperature-sensitive, so Douglass Colony Group workers fabricated a “heat box” to allow the adhesives to be properly stored during freezing temperatures.
“The bulk of the membrane application took place during cold weather,” Greenwell says. “It is difficult to not only work in such a climate but to adhere 80-mil-thick membrane on an oval roof deck was an unprecedented challenge. The final appearance is outstanding.”
In addition to working in cold conditions, the workers installed the sheet metal during the middle of summer when roof temperatures measured as hot as 140 F. Workers adjusted shifts to ensure working conditions were safe at all times while staying on schedule.
A renewed landmark
In January 2020, the Douglass Colony Group crew completed work on the Denver Art Museum on time and without incident. With a heavy emphasis on hand-fabrication and craftsmanship that could not be achieved using machinery, Douglass Colony Group’s experienced team was an undeniable asset to the project’s success.
Although opening the Sie Welcome Center and reopening the Martin Building has been postponed to later this year because of COVID-19 restrictions, the completion of the project expands the museum’s ability to serve the community, welcome guests to Denver, and preserve and present priceless works of art from cultures around the world and throughout history for generations to come.
“The Denver Art Museum is pleased with the work on the roof systems at the new Sie Welcome Center,” says Jena Pruett, communications associate for Denver Art Museum. “Douglass Colony Group delivered on all aspects of what the Denver Art Museum and design team had envisioned from the onset to completion of the project. They were able to take a complex project and turn it into a unique, iconic space that ties in beautifully with other existing buildings. We are excited to have this new addition to our campus and know the structure will be a centerpiece of the Denver community for years to come.”
For exceptional work on the Denver Art Museum, Douglass Colony Group received a 2021 Gold Circle Award from the Roofing Alliance in the Outstanding Workmanship and Innovative Solutions—Low-slope category.
“The most rewarding part of the job was seeing our team’s hard work and countless hours spent designing, coordinating, fabricating and installing come to fruition and into a true piece of art,” Harvey says.
Original Source: https://www.professionalroofing.net